Lighting and Electrical Appliances

Lighting: Artificial lighting is to energy inefficiency what blood pressure is to heart attacks: the silent killer.  Many work and living spaces are artificially lit in excess of recommended wattage per square foot levels which are generally <2 watts per square foot.  Furthermore, unlike computers and monitors or other modern technologies that feature sleep mode capabilities, lights draw 100% of their rated power throughout each period of operation. Contrary to popular belief, turning lights off when not in use does not result in greater energy use due to negligible spikes in energy usage associated with ‘starting up’ a light bulb. As such, frivolous light bulb operation (i.e., leaving them on or turning them on when not needed) represents one of the easiest improvement areas for home energy audits, and the following steps are recommended.

· If the lights don’t need to be on, turn them off. This advice is true whether you’re at work or at home. When you divide a calendar year into three equal 8-hour segments representing a work day, sleep and awake/active hours, it’s easy to see how reduced light usage can quickly translate into big savings.

· Evaluate your wattage per square foot and adjust wattage settings accordingly. Regardless of whether more or less light is needed for a given space, increase utilization of natural light, which more often than not simply requires opening up the blinds (but in a manner that also limits glare).

· If you must use artificial light, select lower wattage desk lamps in lieu of overhead lighting. Switch out your incandescent bulbs for fluorescent bulbs, and eliminate bulbs from fixtures that create over-lit situations (i.e., chandeliers, vanity fixtures, etc.)

Electrical Appliances: It’s embarrassing to have to say it, but if the appliance doesn’t need to be on, turn it off. Every little bit adds up. While you shouldn’t expect a 50% reduction in your power bill from unplugging your cell phone charger (which only draws about one watt/hr when plugged in and about three watts/hr when charging), it nonetheless represents non-essential energy use when not actively charging a phone. However, despite cell phone chargers becoming the poster child for ‘phantom loads’, devices that are more responsible for consuming energy when they are ‘off’ have internal clocks (computer, television, stereo, DVD player, coffee pot, etc.) or heating elements (printers that keep ink warm). Thus, unless these appliances need to be on when they’re not in use (i.e., a network computer that receives security updates after hours, a FAX machine that communicates at night, a television that is programmed for TiVO, etc), it’s best to put these appliances on a power-strip and then turn the power strip off when not in use or physically unplug these appliances from the wall socket.

Some electrical appliances that seem like necessities are actually just objects of convenience. For example, in many modern societies sunlight/heat is used to dry clothing either on clothes lines or using drying racks. Natural drying of clothes requires zero fossil fuels (other than the fuels used to make and ship the clothes line or drying rack) and the payback time for investing in drying racks or a clothes line is generally within a month or two. Although extreme environmentalists would also list hot water, conditioned air and refrigeration in the category of frivolous needs, I consider these items to be essentials for modern life and have already shown how to improve the efficiency of your HVAC and water heating systems.  However, on the topic of refrigeration efficiency I would also add keeping the refrigeration coils debris-free, adjusting thermostat settings in the refrigerator, and avoiding putting hot or warm food in the refrigerator/freezer. The cost-benefit (energy vs. convenience) of other small appliances are easily identified by the kill-a-watt meter due to the ability of the kill-a-watt meter to make users more conscientious of the impact of their appliances (as well as whether or not the appliance is operating properly).

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